In that scene, Nick Fury (Samuel L. Jackson) and Maria Hill (Cobie Smulders) find themselves in the middle of the Thanos-sparked chaos as half the universe's population disappears. Fury manages to use his pager and apparently sends a message to Captain Marvel just as he, too, disappears into dust. Since her film arrives before the next Avengers films, it would seem she's got an important role to play in Avengers 4, possibly saving the universe.

Captain Marvel? Not exactly the best-known superhero ever. But her film will be the 21st in the Marvel Cinematic Universe, and if she's going to get that kind of post-credits attention, fans had best brush up on her dossier before her film comes out.

Who is Captain Marvel?

You can dive deep into her background and history with this explainer. A short version: This iteration of the character, Carol Danvers, was created in 1968, and was an Air Force pilot, CIA agent, security director for NASA and writer. She's also struggled with alcohol, like Iron Man Tony Stark, and her personal battles were depicted in numerous comic-book issues.

Her superpowers came from a Kree alien named Mar-vell, the original Captain Marvel, and include flight, super strength, the ability to absorb and use energy, and to shoot energy blasts and lasers from her hands.

Numerous characters have taken on the Captain Marvel name, and even DC Comics has had an (unrelated) Captain Marvel character (aka Shazam), though to date the Marvel universe doesn't have a "Captain DC."

Release date and plot

Captain Marvel is due out March 9, 2019, in the US and UK (no Australia date yet), about two months before Avengers 4 hits.

But don't let that proximity fool you. The film isn't focusing solely on Captain Marvel finding out about Thanos' slaughter of half the universe (see: Avengers: Infinity War) and leaping in to help. It's set in the 1990s, which may explain why Nick Fury is reaching out to her on a pager, not a smartphone. (Speaking of the 1990s, star Brie Larson was almost born in that decade -- Oct. 1, 1989 -- which makes some of us feel as ancient as an unopened bottle of Zima.)

So what's going on in the film? Marvel reports it's about Carol Danvers taking on the Captain Marvel role to protect the Earth from a galactic war between the Kree and the Skrulls, both alien races familiar to comics readers. (The comic version of this war played out in 1971 and 1972, if you want to consult your archived Avengers issues for possible spoilers.)

Who are the combatants? The Skrulls are a race of shape-shifting aliens that can take on not just the shape, but the memories and powers of those they mimic. The Kree are a scientifically and technologically advanced militaristic race, some of whom have blue skin. Getting in the way of either of them is about as smart as tugging on Superman's cape -- oops, wrong comics company.

As for Captain Marvel herself, you may know star Larson best from her Oscar-winning role as a kidnap victim forced to bear and raise her son in captivity in 2015's Room. She also starred in 2017's Kong: Skull Island.

Backing her up in the film are some familiar faces for Marvel fans, and a few new ones.

Samuel L. Jackson will play a young (pre-eye patch) Nick Fury.

Clark Gregg is returning as S.H.I.E.L.D. agent Phil Coulson, who's dead in the modern Marvel movie timeline, but alive in the 1990s-set film.

Lee Pace returns as Ronan the Accuser, a fanatical member of the Kree alien race who was last seen in Guardians of the Galaxy.

Djimon Hounsou returns as Korath, a Kree ally of Ronan and feared intergalactic hunter, who also appeared in Guardians of the Galaxy.

Annette Bening has signed on, in what will be the four-time Oscar nominee's first-ever comic-book movie. She's reportedly playing a scientist, and Variety reports that scientist is likely to be Carol's mother.